The 1761028-1: The 0.050-inch contact pitch and 0.100-inch row spacing pack more circuits into a smaller shell than a standard D-sub — the footprint is roughly the same as a 15-position standard-density shell but carries 26 signal lines.
The shell is shielded and nickel-plated steel, so it provides EMI containment for the signal bundle — important when the connector passes through a cutout in a metal enclosure. The gold contact finish gives reliable signal-level connections over repeated mating cycles; the 1 A per-contact rating confirms this is a signal-density part, not a power interconnect.
The flange features housing/shell (2-56) threaded inserts plus latchblocks and rails, so the mating plug can be secured with jack-screws or a slide-lock mechanism. The 26 gold-plated phosphor bronze contacts are fixed in the receptacle body; the mating half (a 26-position AMPLIMITE.050 III plug with male pins) carries the crimp or solder contacts.